1. Field of the Invention
The present invention relates to a swivel device and a video display apparatus equipped with the swivel device.
2. Description of Related Art
There is known a swivel device that supports a video display portion of a liquid crystal TV set or the like and turns around the vertical axis so that the direction of the video display portion can be changed as shown in JP-A-6-292106, for example.
JP-A-6-292106 discloses a turn table (a swivel device) equipped with a swivel gear disposed on a base in a pivotable manner around the vertical axis, a swivel frame disposed on the swivel gear in a pivotable manner around the vertical axis, and a motor that drives the swivel gear via a reduction gear mechanism. In this turn table, the swivel frame can be swiveled by a drive force of the motor as well as by a manual operation. The top surface of the swivel gear of the turn table is provided with protrusions, and the peripheral portion of the base is provided with leaf springs on a plurality of positions spaced from each other in the circumferential direction. These leaf springs press the protrusions of the swivel gear to the undersurface of the swivel frame, so that friction resistance is generated between the protrusions of the swivel gear and the undersurface of the swivel frame when the swivel gear turns. Thus, the driving force of the motor is transmitted to the swivel frame via the swivel gear, so that the swivel frame turns around the vertical axis. In addition, when the swivel frame is turned by a manual operation, the protrusions of the swivel gear slide with respect to the undersurface of the swivel frame if a force larger than the friction resistance is exerted in the swivel direction. Therefore, even if the swivel gear generates a swivel resistance due to the reduction gear mechanism, the swivel frame can be turned. In this way, the above-mentioned turn table described in JP-A-6-292106 can change the direction of the video display portion by the driving force of the motor because the swivel frame of the turn table supports the video display portion. In addition, the direction of the video display portion can be changed by a manual operation, too.
However, in the conventional turn table (swivel device) described in JP-A-6-292106, it is necessary to provide the leaf springs at a plurality of positions spaced from each other in the circumferential direction of the base so as to press the protrusions of the swivel gear to the undersurface of the swivel frame. Therefore, there is a problem in that the complicated structure thereof and increases in the number of components and man-hour to produce it cause an increase in the cost.